Electric-arc lamp.



J. H. HALLBBRG.

ELECTRIC ARQ LAMP. APPLICATION FILED MAY 1, 1909.

Patented June 13, 1911.

Inventor: %w Attj UNITED STATES PATENT OFFICE.

JOSEF H. HALLBERG, OF NEW YORK, N. Y., ASSIGNOR TO THE BECK FLAMING LAMPCOMPANY, OF CANTON, NEW YORK, A CORPORATION OF NEW YORK.

ELECTRIC- ARC LAMP.

Specification of letters Patent.

Application filed May 1, 1909. Serial No. 493,250.

To all whom it may concern:

Be it known that I, JOsEF H. HALLBERG, a citizen of the United States,and resident of New York, in the county and State of New York, haveinvented certain new and useful Improvements in Electric-Arc Lamps, ofwhich the following is a specification.

My invention relates to an improvement in arc lamps. In such lamps whenthere occurs for any reason, a sudden abnormal increase of potential atthe lamp terminal before the lamp mechanism has had time to Iced thecarbons or electrodes into contact, the tendency is for the insulationof the lamp to be broken down or the current may jump across an air gap,for example between the lamp terminals, with the result of more or lessinjury to the lamp.

It is the object of the present inventionto prevent this.

My invention is shown in connection with a type of arc lamp, illustratedin my application, Serial Number 438,277 for United States LettersPatent, but it will be understood that the invention is applicable toother types of lamp.

'tion is applied, as this is fully In the drawings, Figure 1 is a sideelevation partly in vertical section of the upper or barrel portion of athe present invention, the actual barrel or cylindrical casing whichincloses the parts being om'tted; and Fig. 2 is an enlargement withimmaterial changes in representation, of the upper portion of Fig. 1.

It is unnecessary to describe in detail the mechanism of the lamp, towhich the invenset forth in the above named application, but it may bestated that ,1 and 2 are the carbons of the lamp, the latter beingmovable angularly, so that its upper end is carried away from carbon 1,to bring the lower ends of the carbons into contact; and that thismovement is accomplished automatically when the lamp} current has beencut oil", by the plunger 3 of the denergized solenoid 4 descending andthereby operating the lazy tongs 5 to carry the rod 6 and consequentlythe attached carbon 2 through an angular movement sufiicient to bringthe end of this carbpn into lamp equipped with contact with carbon 1.The are circuit is from terminal 7 through solenoid 4 to carbon 1 andthence by way of the arc to carbon 2 back to lamp terminal 8.

The present invention consists in providing a circuit across thecarbons, i. e. a circuit in shunt with the arc, adapted to be open whenthe lamp current is on and adapted to almost instantly close when it iscut ofi, so that a continuous path is provided to receive any suddenincrease of potential and thereby prevent breaking down of insulation orjumping of the current, in spite of the fact that the lamp mechanism maynot have had time to feed the carbons into contact.

The specific form of the improvement shown consists of a solenoid 9, inseries with the arc circuit. This solenoid has a vertical plunger core10, having a contact 11 on its lower end which rests on a fixed contact12, when the core drops upon the deenergization of the solenoid. Thesecontacts are preferably of virgin silver. The plunger contact isconnected with lamp terminal 7 by a lead 14:, whereas the fixed contactis connected with the other lamp terminal through aresistance 15 whichis located approximately in line with the solenoid and carries the fixedcontact. When the lamp is energized the solenoid 9, holds its plunger inelevated position with the contacts 11 and 12 separated and therefore nocurrent passes through the shunt circuit.

The instant the lamp current is cut oif and.

. considerably before the lamp mechanism has fed thecarbons intocontact, the core 10 drops closing the contacts and the shunt cir-.

cuit so that any succeeding current has an uninterrupted circuit throughthe lamp. The resistance 15 is such that when the lamp current is againthrown on with the carbonstouching, enough current passes in the arccircuit and through the solenoid 9 to attract its plunger and separatethe contacts 11 and 12, after which all of the current passes throughthe arc circuit.

What I claim as new is In an arc lamp, in combination with the arccircuit, a circuit across the electrodes including a solenoid which isin the arc cirsuit and a resistance disposed spproximately 111 hne Wlththe solenold, sald solenoid having a plunger, 21 contact carried by saidplunger and. connected with one of the lamp terminals, and a fixed.Contact carried Witness my hand this 30th day of April, 1909, at NewYork, N. Y.

JO SEF H. H ALLBERG.

Witnesses 1%. A. FINN, E. W. SCHERR, r.

